Sample tube rack



FIG. 1 is a perspective view of sample tube rack showing my new design;

FIG. 2 is a front side elevational view;

FIG. 3 is a rear side elevational view;

FIG. 4 is a right side elevational view,

FIG. 5 is a left side elevational view;

FIG. 6 is a top plan view;

FIG. 7 is a bottom plan view; and,

FIG. 8 is an exploded view.

The broken lines in the drawings depict portions of the sample tub rack that form no part of the claimed design. 

CLAIM The ornamental design for sample tube rack, as shown and described. 